What fullrange backloaded horn (with optional dipole AMT tweeter on top) to build?

Folks, I need your advice: I want to build a fullrange backloaded horn loudspeaker, preferably 6-8" driver, with low distance from driver edge to upper enclosure edge for placing an ESS AMT-1 Air Motion Transformer on top. The thought is to have kinda dual use loudspeaker, switchable from fullrange to 2-way. I need something giving decent resolution at low listening volume (≤ 70db). I intend to cross it as low as possible (1-2kHz) with steep active filter and DSP EQ.

What driver in what enclosure do you recommend?

Thank you for your thoughts!
 
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Synergy Horn with AMT

767105d1562603326-synergy-horn-amt-bce07cee-cfd0-4720-81ef-3814d1cca03d-jpeg


B&C 6MDN44 midrange
 
Thank you so far!

@ pelanj: Looking at the price tag, saying 'No way' ...

@ xrk971: Well, I'd really love to try that too. :worship: But in my 5x4.5 m (16.4x14.8 ft) listening and living room a 3 ft. deep construction is way too big as I reckon it needs some distance to the rear wall . What are the crossover frequencies, by interest?
 

pelanj

Member
Paid Member
2008-07-17 8:47 am
Hořovice
What is the budget? A pair of Sonido 8" ferite fullrangers is almost less than the linked kit for one box. Sonido Archivy - Audio-DIY

I can also highly recommend the ferite 175 in its recommended horn - see sonido.hu for designs - if you write an e-mail to them, they have many other designs to share. The only issue with the one I have is, that you cannot place a tweeter on top, since the driver is placed lower.
 
@ waxx: Indeed that is one of the candidates for my project. How is low level listening? Most of the fullrange drivers I savoured need relatively high volume to sound right.

@ pelanj: Obviously I got something wrong regarding the Sonido prices. Thanks for clarification. The Sonido BLH designs look very interesting indeed! What driver exactly are you referring to - SFR-200a?
 
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pelanj

Member
Paid Member
2008-07-17 8:47 am
Hořovice
Yes, I have a pair of SFR200A and SFR175 (in the horn that is shown on the Sonido web site - this one: http://sonido.hu/adat_pdf/diy-sfr175-backloaded.pdf). The nice thing about Sonido is, that their response is free of the nasty rise that some FR speakers have. If you would like to get some inspiration, please have a look into the gallery at the Sonido website (Gallery - sonido.hu) and send them an e-mail. I did that and I have like 5 different suggestions for the SFR200A, but no time to choose:) - some designs are here: DIY! - sonido.hu

I actually started to be interested in Sonido when I heard the SFR200A in a folded TQWT. Very natural sound, especially the percussions were awesome. Concerning the low level listening, these are very sensitive, so I recommend a class A amplifier to get the best out of them at low volumes.
 
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@ waxx: Indeed that is one of the candidates for my project. How is low level listening? Most of the fullrange drivers I savoured need relatively high volume to sound right.

The owner use a 3w Line Magnetic EL84 SE amp, but as it was build with my help at my house we also tested it with my Prima Luna Prologue 4 (32w EL34 PP tube amp) and a Marantz PM5004 (45w class AB transistor). in all situation it sounded very good, altough the Prima Luna and the Marantz are way to powerfull for this high efficient driver in a small room. My living room is 8x6x2.5m and there it was already too powerfull. The 3w SE amp was better for this speaker. Your listening room is half that if i'm right so with a few watt it will be enough.

And to give you an other option, a Frugalhorn XL with an Mark Audio Alpair 10M Gen 3 is also a good option. That driver is better on low level than the tangband (wich is still very good) if you ask me, and a bit less efficient (so it's a bit more flexibel on amps). The difference is small (and may be subjective). I run ported boxes now with that driver and i love it.
 
The size of the horn can be made much more compact - depends on what uniform dispersion angle you want - wider is more compact. I had a 45 deg horn and I wanted the directivity to go low so it was big. I can see more compact 20in deep plus a 3in deep rear chamber stuffed with fiberglass working well for a 90deg horn. You could use an 8in woofer instead of a 6in mid and go much deeper - down to say 80Hz for a sub to take over.

The AMT in a horn is almost a full range. The electrical XO freq was 800Hz but acoustically it was 600Hz - so basically a FAST topology.

It's the BEST sounding speaker I have ever heard - very special.
 

mp9

Member
2006-06-07 7:00 am
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And to give you an other option, a Frugalhorn XL with an Mark Audio Alpair 10M Gen 3 is also a good option. That driver is better on low level than the tangband (wich is still very good) if you ask me, and a bit less efficient (so it's a bit more flexibel on amps). The difference is small (and may be subjective). I run ported boxes now with that driver and i love it.
along those lines, my vote would be for cousin of Frugal horn, JOAN horn/MA A12pw X Mundorf AMT23D1.1 DIPOLE AMT or Mundorf AMT23D6.1-C Dipole AMT
 
Gentlemen, I thank you very much for your input! :up:

Looking at the Alpair 10.3 inevitably it's uncle, the Jordan JX92s, comes into mind. Different in parameters, but similar in construction and appearance. I have a well retained pair of those, doing a good job in a pair of Jim Griffin's MiniMonitors as to be seen further down here. They never disappointed me, but their parameters (Qts around 0.5) do not really call for a BLH or TQWT. However, the Alpair 10.3 and 12 AP are on my list of candidates now as well as the Sonidos and the Tang Band. I'll have to boil down that assortment.

Synergy horns are a different breed , but yes: Very, very interesting, especially with some ESS AMT-1s crossed low. On the other hand the 2-way option I mentioned would be thwarted, but as I have RiPol subwoofers being ideal partners for horn speakers ... :rolleyes:

@ xrk971: Never before I cared for directivity as it always was given by the principles of the drivers I have used. Higher directivity is not an issue in my rather small room with quite fixed listening position. Would you guide me to how to design a 90° version of your attempt? I hope I'm not asking for too much.
 
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